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/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (C) 2014 Freescale Semiconductor, Inc.
*/
#ifndef __LINUX_MTD_SPI_NOR_H
#define __LINUX_MTD_SPI_NOR_H
#include <linux/bitops.h>
#include <linux/mtd/cfi.h>
#include <linux/mtd/mtd.h>
#include <linux/spi/spi-mem.h>
/*
* Note on opcode nomenclature: some opcodes have a format like
* SPINOR_OP_FUNCTION{4,}_x_y_z. The numbers x, y, and z stand for the number
* of I/O lines used for the opcode, address, and data (respectively). The
* FUNCTION has an optional suffix of '4', to represent an opcode which
* requires a 4-byte (32-bit) address.
*/
/* Flash opcodes. */
#define SPINOR_OP_WRDI 0x04 /* Write disable */
#define SPINOR_OP_WREN 0x06 /* Write enable */
#define SPINOR_OP_RDSR 0x05 /* Read status register */
#define SPINOR_OP_WRSR 0x01 /* Write status register 1 byte */
#define SPINOR_OP_RDSR2 0x3f /* Read status register 2 */
#define SPINOR_OP_WRSR2 0x3e /* Write status register 2 */
#define SPINOR_OP_READ 0x03 /* Read data bytes (low frequency) */
#define SPINOR_OP_READ_FAST 0x0b /* Read data bytes (high frequency) */
#define SPINOR_OP_READ_1_1_2 0x3b /* Read data bytes (Dual Output SPI) */
#define SPINOR_OP_READ_1_2_2 0xbb /* Read data bytes (Dual I/O SPI) */
#define SPINOR_OP_READ_1_1_4 0x6b /* Read data bytes (Quad Output SPI) */
#define SPINOR_OP_READ_1_4_4 0xeb /* Read data bytes (Quad I/O SPI) */
#define SPINOR_OP_READ_1_1_8 0x8b /* Read data bytes (Octal Output SPI) */
#define SPINOR_OP_READ_1_8_8 0xcb /* Read data bytes (Octal I/O SPI) */
#define SPINOR_OP_PP 0x02 /* Page program (up to 256 bytes) */
#define SPINOR_OP_PP_1_1_4 0x32 /* Quad page program */
#define SPINOR_OP_PP_1_4_4 0x38 /* Quad page program */
#define SPINOR_OP_PP_1_1_8 0x82 /* Octal page program */
#define SPINOR_OP_PP_1_8_8 0xc2 /* Octal page program */
#define SPINOR_OP_BE_4K 0x20 /* Erase 4KiB block */
#define SPINOR_OP_BE_4K_PMC 0xd7 /* Erase 4KiB block on PMC chips */
#define SPINOR_OP_BE_32K 0x52 /* Erase 32KiB block */
#define SPINOR_OP_CHIP_ERASE 0xc7 /* Erase whole flash chip */
#define SPINOR_OP_SE 0xd8 /* Sector erase (usually 64KiB) */
#define SPINOR_OP_RDID 0x9f /* Read JEDEC ID */
#define SPINOR_OP_RDSFDP 0x5a /* Read SFDP */
#define SPINOR_OP_RDCR 0x35 /* Read configuration register */
#define SPINOR_OP_RDFSR 0x70 /* Read flag status register */
#define SPINOR_OP_CLFSR 0x50 /* Clear flag status register */
#define SPINOR_OP_RDEAR 0xc8 /* Read Extended Address Register */
#define SPINOR_OP_WREAR 0xc5 /* Write Extended Address Register */
#define SPINOR_OP_SRSTEN 0x66 /* Software Reset Enable */
#define SPINOR_OP_SRST 0x99 /* Software Reset */
#define SPINOR_OP_GBULK 0x98 /* Global Block Unlock */
/* 4-byte address opcodes - used on Spansion and some Macronix flashes. */
#define SPINOR_OP_READ_4B 0x13 /* Read data bytes (low frequency) */
#define SPINOR_OP_READ_FAST_4B 0x0c /* Read data bytes (high frequency) */
#define SPINOR_OP_READ_1_1_2_4B 0x3c /* Read data bytes (Dual Output SPI) */
#define SPINOR_OP_READ_1_2_2_4B 0xbc /* Read data bytes (Dual I/O SPI) */
#define SPINOR_OP_READ_1_1_4_4B 0x6c /* Read data bytes (Quad Output SPI) */
#define SPINOR_OP_READ_1_4_4_4B 0xec /* Read data bytes (Quad I/O SPI) */
#define SPINOR_OP_READ_1_1_8_4B 0x7c /* Read data bytes (Octal Output SPI) */
#define SPINOR_OP_READ_1_8_8_4B 0xcc /* Read data bytes (Octal I/O SPI) */
#define SPINOR_OP_PP_4B 0x12 /* Page program (up to 256 bytes) */
#define SPINOR_OP_PP_1_1_4_4B 0x34 /* Quad page program */
#define SPINOR_OP_PP_1_4_4_4B 0x3e /* Quad page program */
#define SPINOR_OP_PP_1_1_8_4B 0x84 /* Octal page program */
#define SPINOR_OP_PP_1_8_8_4B 0x8e /* Octal page program */
#define SPINOR_OP_BE_4K_4B 0x21 /* Erase 4KiB block */
#define SPINOR_OP_BE_32K_4B 0x5c /* Erase 32KiB block */
#define SPINOR_OP_SE_4B 0xdc /* Sector erase (usually 64KiB) */
/* Double Transfer Rate opcodes - defined in JEDEC JESD216B. */
#define SPINOR_OP_READ_1_1_1_DTR 0x0d
#define SPINOR_OP_READ_1_2_2_DTR 0xbd
#define SPINOR_OP_READ_1_4_4_DTR 0xed
#define SPINOR_OP_READ_1_1_1_DTR_4B 0x0e
#define SPINOR_OP_READ_1_2_2_DTR_4B 0xbe
#define SPINOR_OP_READ_1_4_4_DTR_4B 0xee
/* Used for SST flashes only. */
#define SPINOR_OP_BP 0x02 /* Byte program */
#define SPINOR_OP_AAI_WP 0xad /* Auto address increment word program */
/* Used for S3AN flashes only */
#define SPINOR_OP_XSE 0x50 /* Sector erase */
#define SPINOR_OP_XPP 0x82 /* Page program */
#define SPINOR_OP_XRDSR 0xd7 /* Read status register */
#define XSR_PAGESIZE BIT(0) /* Page size in Po2 or Linear */
#define XSR_RDY BIT(7) /* Ready */
/* Used for Macronix and Winbond flashes. */
#define SPINOR_OP_EN4B 0xb7 /* Enter 4-byte mode */
#define SPINOR_OP_EX4B 0xe9 /* Exit 4-byte mode */
/* Used for Spansion flashes only. */
#define SPINOR_OP_BRWR 0x17 /* Bank register write */
#define SPINOR_OP_CLSR 0x30 /* Clear status register 1 */
/* Used for Micron flashes only. */
#define SPINOR_OP_RD_EVCR 0x65 /* Read EVCR register */
#define SPINOR_OP_WD_EVCR 0x61 /* Write EVCR register */
/* Status Register bits. */
#define SR_WIP BIT(0) /* Write in progress */
#define SR_WEL BIT(1) /* Write enable latch */
/* meaning of other SR_* bits may differ between vendors */
#define SR_BP0 BIT(2) /* Block protect 0 */
#define SR_BP1 BIT(3) /* Block protect 1 */
#define SR_BP2 BIT(4) /* Block protect 2 */
#define SR_BP3 BIT(5) /* Block protect 3 */
#define SR_TB_BIT5 BIT(5) /* Top/Bottom protect */
#define SR_BP3_BIT6 BIT(6) /* Block protect 3 */
#define SR_TB_BIT6 BIT(6) /* Top/Bottom protect */
#define SR_SRWD BIT(7) /* SR write protect */
/* Spansion/Cypress specific status bits */
#define SR_E_ERR BIT(5)
#define SR_P_ERR BIT(6)
#define SR1_QUAD_EN_BIT6 BIT(6)
#define SR_BP_SHIFT 2
/* Enhanced Volatile Configuration Register bits */
#define EVCR_QUAD_EN_MICRON BIT(7) /* Micron Quad I/O */
/* Flag Status Register bits */
#define FSR_READY BIT(7) /* Device status, 0 = Busy, 1 = Ready */
#define FSR_E_ERR BIT(5) /* Erase operation status */
#define FSR_P_ERR BIT(4) /* Program operation status */
#define FSR_PT_ERR BIT(1) /* Protection error bit */
/* Status Register 2 bits. */
#define SR2_QUAD_EN_BIT1 BIT(1)
#define SR2_QUAD_EN_BIT7 BIT(7)
/* Supported SPI protocols */
#define SNOR_PROTO_INST_MASK GENMASK(23, 16)
#define SNOR_PROTO_INST_SHIFT 16
#define SNOR_PROTO_INST(_nbits) \
((((unsigned long)(_nbits)) << SNOR_PROTO_INST_SHIFT) & \
SNOR_PROTO_INST_MASK)
#define SNOR_PROTO_ADDR_MASK GENMASK(15, 8)
#define SNOR_PROTO_ADDR_SHIFT 8
#define SNOR_PROTO_ADDR(_nbits) \
((((unsigned long)(_nbits)) << SNOR_PROTO_ADDR_SHIFT) & \
SNOR_PROTO_ADDR_MASK)
#define SNOR_PROTO_DATA_MASK GENMASK(7, 0)
#define SNOR_PROTO_DATA_SHIFT 0
#define SNOR_PROTO_DATA(_nbits) \
((((unsigned long)(_nbits)) << SNOR_PROTO_DATA_SHIFT) & \
SNOR_PROTO_DATA_MASK)
#define SNOR_PROTO_IS_DTR BIT(24) /* Double Transfer Rate */
#define SNOR_PROTO_STR(_inst_nbits, _addr_nbits, _data_nbits) \
(SNOR_PROTO_INST(_inst_nbits) | \
SNOR_PROTO_ADDR(_addr_nbits) | \
SNOR_PROTO_DATA(_data_nbits))
#define SNOR_PROTO_DTR(_inst_nbits, _addr_nbits, _data_nbits) \
(SNOR_PROTO_IS_DTR | \
SNOR_PROTO_STR(_inst_nbits, _addr_nbits, _data_nbits))
enum spi_nor_protocol {
SNOR_PROTO_1_1_1 = SNOR_PROTO_STR(1, 1, 1),
SNOR_PROTO_1_1_2 = SNOR_PROTO_STR(1, 1, 2),
SNOR_PROTO_1_1_4 = SNOR_PROTO_STR(1, 1, 4),
SNOR_PROTO_1_1_8 = SNOR_PROTO_STR(1, 1, 8),
SNOR_PROTO_1_2_2 = SNOR_PROTO_STR(1, 2, 2),
SNOR_PROTO_1_4_4 = SNOR_PROTO_STR(1, 4, 4),
SNOR_PROTO_1_8_8 = SNOR_PROTO_STR(1, 8, 8),
SNOR_PROTO_2_2_2 = SNOR_PROTO_STR(2, 2, 2),
SNOR_PROTO_4_4_4 = SNOR_PROTO_STR(4, 4, 4),
SNOR_PROTO_8_8_8 = SNOR_PROTO_STR(8, 8, 8),
SNOR_PROTO_1_1_1_DTR = SNOR_PROTO_DTR(1, 1, 1),
SNOR_PROTO_1_2_2_DTR = SNOR_PROTO_DTR(1, 2, 2),
SNOR_PROTO_1_4_4_DTR = SNOR_PROTO_DTR(1, 4, 4),
SNOR_PROTO_1_8_8_DTR = SNOR_PROTO_DTR(1, 8, 8),
SNOR_PROTO_8_8_8_DTR = SNOR_PROTO_DTR(8, 8, 8),
};
static inline bool spi_nor_protocol_is_dtr(enum spi_nor_protocol proto)
{
return !!(proto & SNOR_PROTO_IS_DTR);
}
static inline u8 spi_nor_get_protocol_inst_nbits(enum spi_nor_protocol proto)
{
return ((unsigned long)(proto & SNOR_PROTO_INST_MASK)) >>
SNOR_PROTO_INST_SHIFT;
}
static inline u8 spi_nor_get_protocol_addr_nbits(enum spi_nor_protocol proto)
{
return ((unsigned long)(proto & SNOR_PROTO_ADDR_MASK)) >>
SNOR_PROTO_ADDR_SHIFT;
}
static inline u8 spi_nor_get_protocol_data_nbits(enum spi_nor_protocol proto)
{
return ((unsigned long)(proto & SNOR_PROTO_DATA_MASK)) >>
SNOR_PROTO_DATA_SHIFT;
}
static inline u8 spi_nor_get_protocol_width(enum spi_nor_protocol proto)
{
return spi_nor_get_protocol_data_nbits(proto);
}
/**
* struct spi_nor_hwcaps - Structure for describing the hardware capabilies
* supported by the SPI controller (bus master).
* @mask: the bitmask listing all the supported hw capabilies
*/
struct spi_nor_hwcaps {
u32 mask;
};
/*
*(Fast) Read capabilities.
* MUST be ordered by priority: the higher bit position, the higher priority.
* As a matter of performances, it is relevant to use Octal SPI protocols first,
* then Quad SPI protocols before Dual SPI protocols, Fast Read and lastly
* (Slow) Read.
*/
#define SNOR_HWCAPS_READ_MASK GENMASK(15, 0)
#define SNOR_HWCAPS_READ BIT(0)
#define SNOR_HWCAPS_READ_FAST BIT(1)
#define SNOR_HWCAPS_READ_1_1_1_DTR BIT(2)
#define SNOR_HWCAPS_READ_DUAL GENMASK(6, 3)
#define SNOR_HWCAPS_READ_1_1_2 BIT(3)
#define SNOR_HWCAPS_READ_1_2_2 BIT(4)
#define SNOR_HWCAPS_READ_2_2_2 BIT(5)
#define SNOR_HWCAPS_READ_1_2_2_DTR BIT(6)
#define SNOR_HWCAPS_READ_QUAD GENMASK(10, 7)
#define SNOR_HWCAPS_READ_1_1_4 BIT(7)
#define SNOR_HWCAPS_READ_1_4_4 BIT(8)
#define SNOR_HWCAPS_READ_4_4_4 BIT(9)
#define SNOR_HWCAPS_READ_1_4_4_DTR BIT(10)
#define SNOR_HWCAPS_READ_OCTAL GENMASK(15, 11)
#define SNOR_HWCAPS_READ_1_1_8 BIT(11)
#define SNOR_HWCAPS_READ_1_8_8 BIT(12)
#define SNOR_HWCAPS_READ_8_8_8 BIT(13)
#define SNOR_HWCAPS_READ_1_8_8_DTR BIT(14)
#define SNOR_HWCAPS_READ_8_8_8_DTR BIT(15)
/*
* Page Program capabilities.
* MUST be ordered by priority: the higher bit position, the higher priority.
* Like (Fast) Read capabilities, Octal/Quad SPI protocols are preferred to the
* legacy SPI 1-1-1 protocol.
* Note that Dual Page Programs are not supported because there is no existing
* JEDEC/SFDP standard to define them. Also at this moment no SPI flash memory
* implements such commands.
*/
#define SNOR_HWCAPS_PP_MASK GENMASK(23, 16)
#define SNOR_HWCAPS_PP BIT(16)
#define SNOR_HWCAPS_PP_QUAD GENMASK(19, 17)
#define SNOR_HWCAPS_PP_1_1_4 BIT(17)
#define SNOR_HWCAPS_PP_1_4_4 BIT(18)
#define SNOR_HWCAPS_PP_4_4_4 BIT(19)
#define SNOR_HWCAPS_PP_OCTAL GENMASK(23, 20)
#define SNOR_HWCAPS_PP_1_1_8 BIT(20)
#define SNOR_HWCAPS_PP_1_8_8 BIT(21)
#define SNOR_HWCAPS_PP_8_8_8 BIT(22)
#define SNOR_HWCAPS_PP_8_8_8_DTR BIT(23)
#define SNOR_HWCAPS_X_X_X (SNOR_HWCAPS_READ_2_2_2 | \
SNOR_HWCAPS_READ_4_4_4 | \
SNOR_HWCAPS_READ_8_8_8 | \
SNOR_HWCAPS_PP_4_4_4 | \
SNOR_HWCAPS_PP_8_8_8)
#define SNOR_HWCAPS_X_X_X_DTR (SNOR_HWCAPS_READ_8_8_8_DTR | \
SNOR_HWCAPS_PP_8_8_8_DTR)
#define SNOR_HWCAPS_DTR (SNOR_HWCAPS_READ_1_1_1_DTR | \
SNOR_HWCAPS_READ_1_2_2_DTR | \
SNOR_HWCAPS_READ_1_4_4_DTR | \
SNOR_HWCAPS_READ_1_8_8_DTR | \
SNOR_HWCAPS_READ_8_8_8_DTR)
#define SNOR_HWCAPS_ALL (SNOR_HWCAPS_READ_MASK | \
SNOR_HWCAPS_PP_MASK)
/* Forward declaration that is used in 'struct spi_nor_controller_ops' */
struct spi_nor;
/**
* struct spi_nor_controller_ops - SPI NOR controller driver specific
* operations.
* @prepare: [OPTIONAL] do some preparations for the
* read/write/erase/lock/unlock operations.
* @unprepare: [OPTIONAL] do some post work after the
* read/write/erase/lock/unlock operations.
* @read_reg: read out the register.
* @write_reg: write data to the register.
* @read: read data from the SPI NOR.
* @write: write data to the SPI NOR.
* @erase: erase a sector of the SPI NOR at the offset @offs; if
* not provided by the driver, SPI NOR will send the erase
* opcode via write_reg().
*/
struct spi_nor_controller_ops {
int (*prepare)(struct spi_nor *nor);
void (*unprepare)(struct spi_nor *nor);
int (*read_reg)(struct spi_nor *nor, u8 opcode, u8 *buf, size_t len);
int (*write_reg)(struct spi_nor *nor, u8 opcode, const u8 *buf,
size_t len);
ssize_t (*read)(struct spi_nor *nor, loff_t from, size_t len, u8 *buf);
ssize_t (*write)(struct spi_nor *nor, loff_t to, size_t len,
const u8 *buf);
int (*erase)(struct spi_nor *nor, loff_t offs);
};
/**
* enum spi_nor_cmd_ext - describes the command opcode extension in DTR mode
* @SPI_NOR_EXT_NONE: no extension. This is the default, and is used in Legacy
* SPI mode
* @SPI_NOR_EXT_REPEAT: the extension is same as the opcode
* @SPI_NOR_EXT_INVERT: the extension is the bitwise inverse of the opcode
* @SPI_NOR_EXT_HEX: the extension is any hex value. The command and opcode
* combine to form a 16-bit opcode.
*/
enum spi_nor_cmd_ext {
SPI_NOR_EXT_NONE = 0,
SPI_NOR_EXT_REPEAT,
SPI_NOR_EXT_INVERT,
SPI_NOR_EXT_HEX,
};
/*
* Forward declarations that are used internally by the core and manufacturer
* drivers.
*/
struct flash_info;
struct spi_nor_manufacturer;
struct spi_nor_flash_parameter;
/**
* struct spi_nor - Structure for defining the SPI NOR layer
* @mtd: an mtd_info structure
* @lock: the lock for the read/write/erase/lock/unlock operations
* @dev: pointer to an SPI device or an SPI NOR controller device
* @spimem: pointer to the SPI memory device
* @bouncebuf: bounce buffer used when the buffer passed by the MTD
* layer is not DMA-able
* @bouncebuf_size: size of the bounce buffer
* @info: SPI NOR part JEDEC MFR ID and other info
* @manufacturer: SPI NOR manufacturer
* @page_size: the page size of the SPI NOR
* @addr_width: number of address bytes
* @erase_opcode: the opcode for erasing a sector
* @read_opcode: the read opcode
* @read_dummy: the dummy needed by the read operation
* @program_opcode: the program opcode
* @sst_write_second: used by the SST write operation
* @flags: flag options for the current SPI NOR (SNOR_F_*)
* @cmd_ext_type: the command opcode extension type for DTR mode.
* @read_proto: the SPI protocol for read operations
* @write_proto: the SPI protocol for write operations
* @reg_proto: the SPI protocol for read_reg/write_reg/erase operations
* @controller_ops: SPI NOR controller driver specific operations.
* @params: [FLASH-SPECIFIC] SPI NOR flash parameters and settings.
* The structure includes legacy flash parameters and
* settings that can be overwritten by the spi_nor_fixups
* hooks, or dynamically when parsing the SFDP tables.
* @dirmap: pointers to struct spi_mem_dirmap_desc for reads/writes.
* @priv: pointer to the private data
*/
struct spi_nor {
struct mtd_info mtd;
struct mutex lock;
struct device *dev;
struct spi_mem *spimem;
u8 *bouncebuf;
size_t bouncebuf_size;
const struct flash_info *info;
const struct spi_nor_manufacturer *manufacturer;
u32 page_size;
u8 addr_width;
u8 erase_opcode;
u8 read_opcode;
u8 read_dummy;
u8 program_opcode;
enum spi_nor_protocol read_proto;
enum spi_nor_protocol write_proto;
enum spi_nor_protocol reg_proto;
bool sst_write_second;
u32 flags;
enum spi_nor_cmd_ext cmd_ext_type;
const struct spi_nor_controller_ops *controller_ops;
struct spi_nor_flash_parameter *params;
struct {
struct spi_mem_dirmap_desc *rdesc;
struct spi_mem_dirmap_desc *wdesc;
} dirmap;
void *priv;
};
static inline void spi_nor_set_flash_node(struct spi_nor *nor,
struct device_node *np)
{
mtd_set_of_node(&nor->mtd, np);
}
static inline struct device_node *spi_nor_get_flash_node(struct spi_nor *nor)
{
return mtd_get_of_node(&nor->mtd);
}
/**
* spi_nor_scan() - scan the SPI NOR
* @nor: the spi_nor structure
* @name: the chip type name
* @hwcaps: the hardware capabilities supported by the controller driver
*
* The drivers can use this function to scan the SPI NOR.
* In the scanning, it will try to get all the necessary information to
* fill the mtd_info{} and the spi_nor{}.
*
* The chip type name can be provided through the @name parameter.
*
* Return: 0 for success, others for failure.
*/
int spi_nor_scan(struct spi_nor *nor, const char *name,
const struct spi_nor_hwcaps *hwcaps);
/**
* spi_nor_restore_addr_mode() - restore the status of SPI NOR
* @nor: the spi_nor structure
*/
void spi_nor_restore(struct spi_nor *nor);
#endif
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